The invention relates to a linear guide with a rail having a plurality of running tracks, and a carriage with at least one sliding element, which is opposite the running tracks and has a surface on the side facing away from the rail that is inclined relative to the travel directions of the linear guide, where an adjuster that is provided between the sliding element and the carriage can be shifted in the travel directions of the linear guide and has a surface resting in shiftable fashion against the inclined surface of the sliding element.
A linear guide of this kind is known from the applicant's “DryLin® T” catalogue of 8/98. It comprises an essentially T-shaped rail and a carriage with a correspondingly designed channel. The rail has two first pairs of running tracks that are opposite one another and perpendicular to the normal load direction of the carriage, and one second pair of running tracks that are opposite one another and perpendicular to the first running tracks. Sliding: elements made of a highly wear-resistant plastic with a low coefficient of friction are provided in the carriage opposite the running tracks. The sliding elements are wedge-shaped in construction with one surface that is next to the running track and normal to the load direction of the carriage, and an opposite inclined surface against which wedge-shaped adjusters can be pressed against. In order to adjust a clearance both in the normal load direction of the carriage and transverse thereto, the adjusters can be pressed against the inclined surface of the sliding elements by means of a set screw, whereby the associated sliding element, the wider end of which is opposite the set screw and against an abutment of the carriage, is moved towards the rail and thus reduces the clearance between the carriage and the rail at the corresponding bearing point By loosening the set screw, the clearance between the carriage and the rail can be increased at the corresponding bearing point. Expediently, the adjuster is pushed back by a compression spring when the set screw is loosened.
Instead of two running tracks, whose surface normals are opposite to the normal load direction of the carriage, the rail can, in case of smaller loads, also have just one centrally located running track and one corresponding sliding element opposite to it. In contrast to the arrangement described above, the wedge-shaped sliding elements can also be provided at other bearing points of the linear bearing where it is desirable to adjust the clearance.
In the known linear guides, the clearance is usually adjusted at the factory by the manufacturer. This pre-setting can be made on the basis of the displacement force of the carriage. In many cases, however, is it necessary for the customer to readjust the bearing clearance. Because three bearing points can be readjusted with the help of the set screws, this adjustment and control must be very precise. There is a risk of excessively increasing or decreasing the clearance of one of the bearing points during readjustment.